Fifty years ago, Lyndon Baines Johnson delivered one of the most powerful pieces of oratory in presidential history. Standing before Congress at 9 p.m. on March 15, just a few days after the shocking violence that civil-rights protesters confronted during the march over the Edmund Pettus Bridge on “Bloody Sunday” in Selma, Johnson called on members of both parties to pass a bill that ensured the federal government would take the steps that were necessary to protect voting rights.

Delivering that speech was a courageous decision. When the grassroots civil-rights movement tried to force Johnson’s hand by creating unbearable pressure to send a voting-rights bill to Congress, the president might have ignored or stifled their dissent. Instead, he fully embraced their cause by connecting himself and his White House to the fate of this legislation. He didn’t equivocate. Despite strong opposition in Washington to the federal government committing itself to the protection of African American voters, Johnson delivered a powerful speech that left no doubt of where he stood in this debate.

The speech was a response to mounting public pressure to do something about the violence against voting-rights protesters that Americans had seen on their television screens. Until that moment, President Johnson had favored a major voting-rights bill but had insisted that he wanted to wait until later in the year before sending it to Congress. When Martin Luther King Jr. implored the president to move sooner in January for fear that the window of opportunity for a bill would pass (liberals wanted to take every advantage of the 1964 election landslide victory for Democrats), Johnson said that he didn’t think Congress could handle another civil rights measure so soon after the Civil Rights Act of 1964. Johnson also worried that moving too soon with voting-rights legislation would tie up other major bills like Medicare and federal education assistance. These and other bills, in his mind, were essential to achieving racial justice.

“Bloody Sunday” made it impossible for Johnson to wait any longer. Liberal Democrats warned they would propose a bill on their own if Johnson did not. Some congressional Republicans said the same. Voting rights was an idea whose time had come.

President Johnson had legislation ready to go. His Attorney General, Nicholas Katzenbach, had been negotiating the outline of a bill with Senators Mansfield and Dirksen in late February and the basic outlines of a deal were already in place.

The president met with the congressional leadership on March 14. Speaker McCormack invited the president to appear before a joint session of Congress to speak about voting rights. This was something that was usually reserved for national emergencies, such as a president calling for a declaration of war. Johnson took McCormack up on the offer, though Senators Dirksen and Mansfield feared the speech would look like the president was trying to intimidate legislators. McCormack, the 73-year-old New Deal Democrat from Massachusetts, disagreed. “I don’t think your coming before the Congress would be a sign of panic,” he said. “I think it would help.”

The speech was written at break-neck speed. On the morning of March 15, presidential confidante Jack Valenti asked the 33-year-old Richard Goodwin, who had spent the previous night socializing and drinking, to write the speech. Valenti had assigned the job to someone else but Johnson said he wanted Goodwin. “Don’t you know that a liberal Jew has his hands on the pulsebeat of America?” the president told Valenti.

Goodwin had about eight hours to finish the job. He pounded on his typewriter, with the images he had seen on television at the forefront of his mind. Goodwin didn’t wrap up until about 7 p.m. He went so late into the day that he didn’t have time to do any rewrites. He also didn’t want to turn over the speech until the very end so that the president would not have time to tamper with the text.

As Johnson drove in the presidential limousine to Capitol Hill, he could see civil-rights protesters on the streets waving their banners and singing their songs, still fearful about what the president was going to say and whether he would commit to the bill.

When Johnson walked to the podium in the well of the House of Representatives, legislators were sitting on the edge of their seats, eager to hear what he would say. Over 70 million Americans tuned in. The final text of the speech was delivered so late that it could not be all loaded into the teleprompter. Johnson spoke from his black notebook instead.

Johnson opened the speech by stressing the need for the nation to move beyond any kind of divisions over this issue. The right to vote should be a fundamental part of American politics. This was not a Democratic or Republican issue, it was an American problem. “I speak tonight for the dignity of man and the destiny of Democracy. I urge every member of both parties, Americans of all religions and of all colors, from every section of this country, to join me in that cause.”

Although it took approximately five minutes before the first round of applause, most legislators couldn’t stop clapping for the rest of the address, offering 39 rounds of applause, including two standing ovations). Johnson, who loved to keep track of the clapping, was energized. Minnesota Senator Walter Mondale recalled that, “from the first words, I knew the evening was going to be historic.”

In the speech, Johnson situated the struggle for civil rights in the “unending search for freedom” that had been integral to the American tradition since Lexington and Concord. He spoke about voting rights as part of the American tradition. This was a powerful message in an era when southerners dismissed civil-rights protesters as “agitators” and “radicals,” often accusing them of being communists. Johnson did not equivocate about the urgent need for legislation. “This time, on this issue,” the president said, “there must be no delay, no hesitation, and no compromise with our purpose.”

Using words that sent shudders through the spines of many southern whites who were still lining the streets of their communities to attack civil-rights protesters, Johnson gave full credit to the movement. “The real hero of this struggle is the American Negro. His actions and protests, his courage to risk safety and even to risk his life, have awakened the conscience of this nation. His demonstrations have been designed to call attention to injustice, designed to provoke change, designed to stir reform. He has called upon us to make good the promise of America.”

Johnson insisted that every citizen had to embrace the issue at the forefront of the protests. He rejected the wall separating civil-rights activists from the rest of the nation, including the White House. “There is no Negro problem. There is a no Southern problem. There is no Northern problem. There is only an American problem.” As the president told Congress, “their cause must be our cause, too.” In the most powerful moment of the evening, Johnson identified himself and his audience with the protesters in Selma: “Because it is not just Negroes, but really it is all of us, who must overcome the crippling legacy of bigotry and injustice.” Using the mantra of the civil-rights movement, he added, “And we shall overcome.” With those words, the movement and the president of the United States had become one and the same.

When the speech ended most legislators were elated. Senate Majority Leader Mike Mansfield shed some tears. New York Representative Emanuel Celler, 76 years old and a long time civil-rights champion, jumped up to shake Johnson’s hand, and assured the president that his House Judiciary Committee would get to work on the bill right away. One White House advisor recalled that “in the galleries, Negroes and whites wept unabashedly.” Senator Allan Ellender of Louisiana, a conservative southerner, slumped down in his seat.

John Lewis watched the speech seated next to Martin Luther King in a private home in Selma. “And the tears came down his face,” Lewis recalled. “Dr. King started crying and we all cried.” When Johnson returned to the White House he learned from his staff that ordinary Americans had tied up the telephone lines to let him know how inspired they were by his words.

Johnson was in a celebratory mood that night, realizing the speech had been a home run. He was still greatly concerned, however, about the opposition that would soon rear its head. When his friend, the businessman Tom Watson called to tell him it was the best speech he had ever given, and really the best of its kind, one that “thrilled” the entire nation, Johnson said it had a “good reaction in the country, but I don’t know how long it will last ... lots of trouble.”

Johnson’s fears proved prescient. But it was because, as a creature of Congress, he knew how ephemeral the moment would likely be that he moved so swiftly to capitalize on the public pressure and to convert it into legislation. The president’s daughter, Lynda Bird, told reporters, “It was just like that hymn, ‘Once to every man and nation comes a moment to decide.'” With this speech, the civil rights movement and the White House—along with congressional supporters—formed a powerful, singular force that pushed the measure through the House and Senate.

“What happened last week,” noted the editors of Life magazine, “shows how public indignation, sweeping the country like chain lightening, can force a wise and necessary action that had been balked by partisanship and governmental apathy for nearly a hundred years.”

There have been too few moments like this. Too often, presidents have tried to resist when grassroots movements create pressure for political action. They see the activists as politically naïve and essentially incompetent when it comes to “real” politics.

But sometimes the grassroots activists know exactly what they are doing. They are spot-on when making their arguments about what Washington needs to do. And sometimes, like on March 15, a president understands this and reacts by joining them rather than pushing them aside. As the nation today tries to deal with so many huge problems—ranging from economic inequality to immigration, to racism within urban police forces—this is a speech that we should look back to for inspiration and guidance.

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